The RNA polymerase begins transcription at the initiation site, which is located in a promoter. The promoter is a specific region in the DNA strand that is recognized by the polymerase. In eukaryotes, RNA polymerase II locates the promoter by the presence of theTATA box with its base sequence TATAAA. The TATA sequence tells the transcription enzyme that the sequence to be transcribed is only about 30 base pairs away, in the 5' direction (often referred to as downstream). Sequences such as the TATA box, which occur in almost all living organisms, are also known as consensus sequences. These sequences always have the same meaning! The TATA box not only indicates the position of the gene, but also on which strand the information is located. In fact, the genes can be located on both strands, but each gene is only read in the 5' direction and the mRNA is synthesized from 5' to 3'.
During elongation, a pre-messenger RNA is synthesized. The RNA polymerase stops at the termination site of transcription. The pre-messenger RNA then matures into mRNA, which istranslated into a protein on ribosomes in the cytoplasm(translation).